1. Field of the Invention
The invention relates to an electric power storage and delivery system. More particularly, the invention relates to an electric power storage and delivery system suitable for both extended low current and short-term high current delivery, featuring improvements in the overall system power to weight ratio and configuration flexibility.
2. Description of Related Art
Battery chemistries may be selected according to a desired energy storage capacity and/or energy delivery characteristic. A battery with a chemistry selected for sustained low current delivery, an energy battery, typically has a higher total energy capacity and lower weight than a battery with a chemistry capable of delivering high current levels for significantly shorter periods, a power battery. Further, a low current delivery battery may require a similar low current charge input while a high current delivery battery may accept higher charge currents. Different battery chemistries may also have different temperature operating ranges.
Many electrical systems have electric power requirements with energy demand profiles including both low and high current levels. For example, an electric vehicle draws high current levels during acceleration and lower current levels for extended periods once a cruising speed is reached. Alternatively, communications and/or surveillance systems may draw low current levels for extended periods while in a standby/monitoring mode and high current levels during an active mode that is event triggered/engaged only intermittently for example for report/acknowledgment purposes.
Competition in the electric energy storage industry has focused attention on improving system flexibility, energy storage capacity and/or reduction of overall system weight. Therefore, it is an object of the invention to provide an electric energy storage arrangement that overcomes deficiencies in the prior art.